UT521 USERS MANUAL
11
6. Measure method
Warning
When the Tester carry out earth resistance testing, the distance
between E and C have the maximum voltage around 50V volt.
Do not touch the external part of test leads and auxiliary earth
stake in order to avoid shock hazard.
6.1
Precision Measurement (using standard test leads for measurement):
a. place 2 ground stakes in earth/dirt. Minimum distance between earth electrode(E),
probe(P) and auxiliary earth (C) should be 5-10 meter apart, as below connection
figure 2:
(Attention:ensure the ground stakes in the moisture soil. If the soil is too dry, it
need to fill-in sufficient water. Rock or sand also needs moisture before testing.
If the testing site is inside the urban city with concrete cover which is hard to
put in the ground stakes, it can use 25cm X 25 cm two steel plates (or using
the existing ground stakes) place horizontally in concrete surface, and cover
by moisture towel with sufficient water, replace measurement earth, it still can
make measurement in general situation.)
